CN113594234B - Preparation method of gallium oxide Schottky diode with low turn-on voltage - Google Patents
Preparation method of gallium oxide Schottky diode with low turn-on voltage Download PDFInfo
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- AJNVQOSZGJRYEI-UHFFFAOYSA-N digallium;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Ga+3].[Ga+3] AJNVQOSZGJRYEI-UHFFFAOYSA-N 0.000 title claims abstract description 130
- 229910001195 gallium oxide Inorganic materials 0.000 title claims abstract description 125
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- XOYLJNJLGBYDTH-UHFFFAOYSA-M chlorogallium Chemical compound [Ga]Cl XOYLJNJLGBYDTH-UHFFFAOYSA-M 0.000 claims description 15
- 241000252506 Characiformes Species 0.000 claims description 13
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- 229910052733 gallium Inorganic materials 0.000 description 1
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- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
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- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 1
- 229910001887 tin oxide Inorganic materials 0.000 description 1
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- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
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- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
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- H01L29/6609—Diodes
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Abstract
The invention discloses a preparation method of a gallium oxide Schottky diode with low turn-on voltage, which mainly solves the problem of high turn-on voltage of the gallium oxide Schottky diode manufactured by the existing method, and the implementation scheme is as follows: cleaning the gallium oxide substrate; carrying out surface restoration pretreatment on the surface of the cleaned gallium oxide substrate, and growing a gallium oxide epitaxial layer on the front surface of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) technology; depositing ohmic cathode metal on the back surface of the gallium oxide substrate by adopting magnetron sputtering, and carrying out ohmic annealing on the ohmic cathode metal; performing laughing gas inductive coupling plasma treatment on the gallium oxide epitaxial layer, and forming an anode pattern by adopting photoetching; and adopting electron beam evaporation to deposit schottky anode metal according to the anode pattern, and completing device manufacture. The invention reduces the starting voltage of the Schottky diode; the electron mobility of the drift layer is improved, so that the on-resistance is reduced, and the method can be used for high-power, high-voltage and high-frequency rectification.
Description
Technical Field
The invention belongs to the technical field of semiconductor devices, and particularly relates to a manufacturing method of a gallium oxide Schottky diode.
Technical Field
Gallium oxide is a third generation novel semiconductor material, and the gallium oxide semiconductor material can be used for preparing high-power devices due to the characteristics of large forbidden bandwidth of 4.6-4.9eV and critical breakdown field strength of 8 MV/cm. And the gallium oxide power device has the advantages of high breakdown voltage, high working bearing environment, strong radiation resistance and the like. With the continuous progress of modern science and technology, in the fields of communication, power electronics, signal processing, aerospace and the like, the performance of power devices of traditional third-generation semiconductor GaN and SiC cannot meet the requirement of higher working performance. The gallium oxide power device, gaN and SiC are in the same voltage resistance, the on-resistance is lower, the power consumption is smaller, and the gallium oxide power device has a higher Barlichia value.
Gallium oxide power devices currently have mainly diodes and triode MOSFETs, where the diodes have mainly schottky diodes and heterojunction pn diodes. Other P-type semiconductor materials, such as nickel oxide, copper oxide, tin oxide, and n-type gallium oxide, are currently used to make heterojunction pn diodes in combination, because P-type doping of gallium oxide is currently difficult to achieve. The turn-on voltage is an important device parameter of the diode, and the smaller the turn-on voltage is, the better the device performance is. The pn diode is operated by using few photons, so that the turn-on voltage of the pn diode is larger, the turn-off speed of the diode is reduced, the turn-off time is long, and the turn-off loss is larger. The schottky diode manufactured by using the metal-semiconductor junction principle formed by metal-semiconductor contact sequentially comprises a cathode ohmic metal layer 1, a heavily doped oxygen gallium substrate 2, a lightly doped epitaxial gallium oxide layer 3 and an anode schottky metal layer 4 from bottom to top as shown in fig. 1. Although the diode has a lower turn-on voltage than a pn diode, the turn-on voltage of a conventional gallium oxide schottky diode used in a high-frequency circuit is still higher, and the requirements of low turn-on voltage, fast switching speed and low energy consumption can not be met.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a preparation method of a gallium oxide Schottky diode with low starting voltage so as to improve the switching speed and reduce the energy consumption.
The technical idea of the invention is as follows: the surface damage of the gallium oxide substrate is repaired by carrying out surface repair pretreatment on the gallium oxide substrate, so that a high-quality low-doped gallium oxide epitaxial layer can be grown conveniently; the gallium oxide epitaxial layer surface is treated by laughing gas inductive coupling plasma technology, so that Ga-N covalent bonds are formed on the surface of the gallium oxide epitaxial layer, namely, a thin gallium nitride layer, thereby realizing the purpose of the invention.
According to the above thought, the technical scheme of the invention is as follows:
1. the manufacturing method of the gallium oxide Schottky diode with low starting voltage is characterized by comprising the following steps:
1) Sequentially cleaning the gallium oxide substrate (2) by acetone-isopropanol-deionized water;
2) The surface of the cleaned gallium oxide substrate (2) is subjected to surface restoration pretreatment so that the surface damage is restored, and a high-quality low-doped gallium oxide epitaxial layer is grown conveniently;
3) Carrying out epitaxial light doping on the front side of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) method to form a gallium oxide layer (3), depositing ohmic cathode metal (1) on the back side by adopting magnetron sputtering, and carrying out ohmic annealing on the ohmic cathode metal (1);
4) Carrying out laughing gas inductively coupled plasma technology treatment on the epitaxial gallium oxide layer (3) to form Ga-N covalent bonds on the surface of the epitaxial gallium oxide layer, namely a thin gallium nitride layer;
5) And forming an anode pattern on the epitaxial layer (3) after being treated by the laughing gas inductively coupled plasma technology by adopting a photoetching process, and adopting electron beam evaporation to deposit schottky anode metal (4) according to the anode pattern to finish the device manufacturing.
Preferably, the pretreatment of surface repair is performed on the surface of the cleaned gallium oxide substrate (2) in the step 2), and the following is realized:
2a) Immersing the cleaned gallium oxide substrate (2) into a piranha solution prepared by mixing concentrated sulfuric acid with the concentration of 98% and hydrogen peroxide with the concentration of 30% according to the proportion of 3:1, and immersing for 10-40 minutes;
2b) And (3) annealing the gallium oxide substrate treated by the piranha in an oxygen atmosphere, wherein the annealing temperature is 600-1000 ℃ and the annealing time is 10-60 minutes.
Preferably, the 4) performs laughing gas inductively coupled plasma technology treatment on the epitaxial layer gallium oxide (3), and the process conditions are as follows: the power is 50-500W, the laughing gas flow is 20-150sccm, the pressure is 4-20mtorr, the ambient temperature is 25-150 ℃, and the time is 2-20 minutes.
Compared with the prior art, the invention has the following advantages:
first, compared with the conventional gallium oxide schottky diode preparation method, the method provided by the invention has the advantages that the surface of the gallium oxide substrate is subjected to repair pretreatment before the epitaxial growth of the gallium oxide epitaxial layer, so that the gallium oxide molecules on the surface of the substrate are arranged more smoothly, the surface characteristics are optimized, and the low-doped gallium oxide epitaxial layer with higher quality can be grown in the subsequent process.
Secondly, compared with the traditional gallium oxide Schottky diode preparation method, the gallium oxide epitaxial layer below the anode is subjected to laughing gas inductive coupling plasma technology treatment, so that Ga-N covalent bonds are formed on the surface of the gallium oxide epitaxial layer, namely, a thin gallium nitride layer, and therefore, the work function difference between metal and semiconductor can be reduced, and the starting voltage of the Schottky diode is further reduced; and the electron mobility of the drift layer is improved, thereby reducing the on-resistance.
Third, compared with the conventional gallium oxide Schottky diode preparation method, the method for preparing the gallium oxide Schottky diode is simple in preparation and suitable for industrial production.
Description of the drawings:
fig. 1 is a schematic diagram of a low turn-on voltage gan schottky diode according to the present invention;
fig. 2 is a flow chart of an implementation of the present invention for fabricating the gallium oxide schottky diode of fig. 1.
Fig. 3 is a graph of forward characteristics of a conventional schottky diode and the schottky diode of the invention.
The specific embodiment is as follows:
in order to more clearly illustrate the technical solutions in the embodiments of the present invention, the present invention is further described below with reference to the drawings, which are required to be used in the description of the embodiments and the techniques of the present invention. However, it will be apparent to one skilled in the art that the present invention is not limited to these embodiments and that the present invention may be practiced in other embodiments that depart from these specific details.
Referring to fig. 1, a conventional low turn-on voltage gallium oxide schottky diode includes, from bottom to top: the cathode ohmic metal 1 of the Schottky diode, the gallium oxide substrate 2, the gallium oxide lightly doped epitaxial layer 3 and the anode Schottky metal 4 of the Schottky diode. Wherein, ti/Au is adopted as the metal of the cathode ohmic metal 1 of the Schottky diode, the thickness of Ti is 20nm, and the thickness of Au is 400nm; the gallium oxide substrate 2 had a thickness of 650 μm and a doping concentration of 2X 10 19 m -3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the gallium oxide lightly doped epitaxial layer 3 is 10 μm, and the doping concentration is 3×10 16 m -3 The method comprises the steps of carrying out a first treatment on the surface of the The metal of the Schottky diode anode Schottky metal 4 is Ni/Au, the thickness of Ni is 45nm, and the thickness of Au is 400nm.
Referring to fig. 2, the method of fabricating the device structure of fig. 1 of the present invention provides three embodiments as follows:
embodiment one: making gallium oxide substrate with thickness of 650 μm and effective doping carrier concentration of 10 18 cm -3 . The thickness of the lightly doped gallium oxide epitaxial layer is 10 mu m, and the doped carrier concentration is 10 16 m -3 . And the gallium oxide Schottky diode is used for carrying out the laughing gas inductively coupled plasma treatment on the epitaxial layer gallium oxide (3) under the conditions of 100W of power, 40sccm of laughing gas flow, 8mtorr of pressure, 25 ℃ of ambient temperature and 2 minutes of treatment time.
Step one: and cleaning the gallium oxide substrate.
The gallium oxide substrate 2 is selected to have a thickness of 650 mu m and an effective doping carrier concentration of 10 18 cm -3 The doping ion is Sn ion.
Ultrasonic treatment was performed for 5 minutes using acetone-isopropyl alcohol-deionized water, respectively, and then blow-drying was performed using nitrogen gas.
Step two: the surface of the gallium oxide substrate 2 is subjected to pretreatment for repair.
Firstly, preparing a piranha solution from 98% concentrated sulfuric acid and 30% hydrogen peroxide according to a ratio of 3:1, and immersing the cleaned gallium oxide substrate 2 in the piranha solution for 10 minutes;
then, deionized water is used for washing away the residual piranha solution of the flakes, and then nitrogen is used for drying;
finally, annealing was performed using an annealing furnace in an oxygen atmosphere at an annealing temperature of 600 ℃ for 10 minutes.
Step three: and growing a gallium oxide epitaxial layer on the front surface of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) method.
Firstly, HCl and high-purity metal Ga are reacted at 850 ℃ to generate GaCl and GaCl 3 ；
Then, gaCl and GaCl are mixed 3 React with oxygen at 500-650 ℃ to generate a gallium oxide substrate 2 with a thickness of 10 mu m and a doped carrier concentration of 10 16 m -3 Gallium oxide epitaxial layer 3.
And step four, preparing cathode ohmic metal.
And depositing metal Ti/Au on the back surface of the gallium oxide substrate 2 by adopting a magnetron sputtering method, wherein the thickness of a first layer Ti close to the gallium oxide substrate layer is 20nm, and the thickness of a second layer Au metal is 400nm, so as to form the cathode ohm 1.
Step five: and annealing the cathode ohmic metal in a nitrogen atmosphere by using an annealing furnace, wherein the annealing temperature is 470 ℃, and the annealing time is 1 minute.
Step six: and (5) performing surface treatment on the laughing gas inductively coupled plasma.
And (3) performing laughing gas plasma nitrogen injection on the epitaxial layer for 2 minutes under the conditions that the power is 50W, the laughing gas flow is 20sccm, the pressure is 4mtorr and the environment temperature is 25 ℃ by utilizing an inductive coupling plasma technology on the gallium oxide epitaxial layer.
Step seven: anode schottky metal 4 was prepared.
Firstly, preparing an anode pattern on a gallium oxide epitaxial layer subjected to surface treatment of laughing gas inductively coupled plasma by using a photoetching technology;
then, metal Ni/Au was deposited on the anode pattern by electron beam evaporation, and the thickness of the first metal Ni layer was 45nm and the thickness of the second metal Au layer was 400nm.
And finally, adopting N-methyl pyrrolidone solution to wash out photoresist, and completing the manufacture of the device.
Embodiment two: the thickness of the gallium oxide substrate is 300 mu m, and the effective doping carrier concentration is 10 20 cm -3 The thickness of the lightly doped gallium oxide epitaxial layer is 3 mu m, and the doped carrier concentration is 10 17 m -3 . Under the conditions that the power is 200W, the smile flow is 60sccm, the pressure is 10mtorr, the ambient temperature is 50 ℃, and the treatment time is 4 minutes, the epitaxial layer gallium oxide (3) is subjected to the smile inductively coupled plasma treatment.
Step 1: and cleaning the gallium oxide substrate.
The thickness of the selected material is 300 mu m, and the effective doping carrier concentration is 10 20 cm -3 Gallium oxide substrate 2 doped with Sn ions was sonicated with acetone-isopropyl alcohol-deionized water for 5 minutes in ultrasound, respectively, and then blow-dried with nitrogen gas.
Step 2: the surface repair pretreatment of the gallium oxide substrate 2.
Firstly preparing concentrated sulfuric acid with the concentration of 98% and hydrogen peroxide with the concentration of 30% into a piranha solution according to the ratio of 3:1, and immersing the cleaned gallium oxide substrate 2 in the piranha solution for 20 minutes; washing the residual piranha solution with deionized water, and drying with nitrogen; and then annealing for 30 minutes in an oxygen atmosphere at 800 ℃ in an annealing furnace.
Step 3: and growing a gallium oxide epitaxial layer on the front surface of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) method.
HCl and high-purity metal Ga are reacted at 850 ℃ to generate GaCl and GaCl 3 The method comprises the steps of carrying out a first treatment on the surface of the And then GaCl and GaCl are added 3 With oxygen at 500-650deg.CThe reaction produced a thickness of 3 μm on the front side of the gallium oxide substrate 2, a doped carrier concentration of 10 17 m -3 Gallium oxide epitaxial layer 3.
Step 4, manufacturing cathode ohm 1
The specific implementation of this step is the same as step four of embodiment 1.
Step 5: the cathodic ohmic metal was annealed at 470 ℃ for 1 minute using an annealing furnace under nitrogen atmosphere.
Step 6: and carrying out laughing gas inductive coupling plasma surface treatment on the gallium oxide epitaxial layer.
And (3) performing laughing gas plasma nitrogen injection on the gallium oxide epitaxial layer by utilizing an inductive coupling plasma technology under the conditions that the power is 300W, the laughing gas flow is 100sccm, the pressure is 12mtorr and the environment temperature is 100 ℃, wherein the injection time is 12 minutes.
Step 7: anode schottky metal 4 was prepared.
Preparing an anode pattern on the gallium oxide epitaxial layer after the surface treatment of the laughing gas inductively coupled plasma by using a photoetching technology; depositing metal Ni/Au on the anode pattern by adopting an electron beam evaporation method, wherein the thickness of the first layer of metal Ni is 45nm, and the thickness of the second layer of metal Au is 400nm; the photoresist was then rinsed off with acetone to complete the device fabrication.
Embodiment III: the thickness of the gallium oxide substrate is 600 mu m, and the effective doping carrier concentration is 10 18 cm -3 The doped ion type is Sn ion, the thickness of the lightly doped gallium oxide epitaxial layer is 15 mu m, and the doped carrier concentration is 10 16 m -3 And the gallium oxide Schottky diode is used for carrying out the smile inductively coupled plasma treatment on the epitaxial gallium oxide (3) under the conditions of 300W of power, 80sccm of smile flow, 12mtorr of pressure, 60 ℃ of ambient temperature and 6 minutes of treatment time.
And step A, cleaning the gallium oxide substrate.
A1 A gallium oxide substrate with a thickness of 600 μm and an effective doping carrier concentration of 10 18 cm -3 The doping ion is Sn ion;
a2 Respectively sonicated with acetone-isopropanol-deionized water for 5 minutes in ultrasound, and then blow-dried with nitrogen.
And B, carrying out surface repair pretreatment on the gallium oxide substrate.
B1 Preparing a piranha solution by using 98% concentrated sulfuric acid and 30% hydrogen peroxide according to a ratio of 3:1;
b2 Immersing the gallium oxide substrate in the piranha solution for 40 minutes, washing away the residual piranha solution of the flakes by using deionized water, and drying by using nitrogen;
b3 Using an annealing furnace under an oxygen atmosphere, wherein the annealing temperature is 1000 ℃ and the annealing time is 60 minutes.
And C, growing a gallium oxide epitaxial layer on the front surface of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) method.
C1 Reaction of HCl with high-purity metal Ga at 850 ℃ to produce GaCl and GaCl 3 ；
C2 GaCl and GaCl) 3 React with oxygen at 500-650 ℃ to generate a gallium oxide epitaxial layer which is deposited on a gallium oxide substrate (2), the thickness of the epitaxial layer is 15 mu m, and the concentration of doped carriers is 10 16 m -3 。
And D, preparing cathode ohmic metal.
The specific implementation of this step is the same as step four of embodiment 1.
And E, annealing the cathode ohmic metal in a nitrogen atmosphere by using an annealing furnace, wherein the annealing temperature is 500 ℃, and the annealing time is 1 minute.
And F, performing laughing gas inductive coupling plasma surface treatment on the gallium oxide epitaxial layer.
And (3) performing laughing gas plasma nitrogen injection on the gallium oxide epitaxial layer by utilizing an inductive coupling plasma technology under the conditions of 500W of power, 150sccm of laughing gas flow, 20mtorr of pressure and 150 ℃ of environment temperature for 20 minutes.
And G, preparing anode Schottky metal.
G1 Preparing an anode pattern on the gallium oxide epitaxial layer subjected to the surface treatment of the laughing gas inductive coupling plasma by using a photoetching technology, and then depositing schottky anode metal Ni/Au on the anode pattern by adopting electron beam evaporation, wherein the thickness of the first layer of metal Ni is 45nm, and the thickness of the second layer of metal Au is 400nm;
g2 The photoresist is washed out by adopting N-methyl pyrrolidone solution, and the device preparation is completed.
The effect of the invention can be further illustrated by the following experimental results:
the conventional schottky diode and the schottky diode prepared in the first embodiment of the present invention were tested using a Keithley 4200 test apparatus, and the experimental results obtained the forward characteristic curves of the diode, and the results are shown in fig. 3.
As can be seen in FIG. 3, the current density is taken to be 1A/cm 2 The corresponding voltage is used as the starting voltage of the diode, the starting voltage of the traditional gallium oxide Schottky diode is 0.8V, and the starting voltage of the device prepared by the invention is 0.6V. Compared with the traditional Schottky diode, the turn-on voltage is reduced by 25%, and the on current is also improved. The preparation method provided by the invention can effectively reduce the starting voltage of the gallium oxide Schottky diode and improve the on-state current.
The foregoing description is only three specific examples of the invention and does not constitute any limitation of the invention, and it will be apparent to those skilled in the art that various modifications and changes in form and detail may be made without departing from the principles and construction of the invention, for example, the anodic schottky metal preparation method is not limited to electron beam evaporation, but may be employed by any of magnetron sputtering or thermal evaporation, etc., as long as the principles and aspects of the invention are understood; the method for preparing the cathode ohmic metal is not limited to magnetron sputtering, and any method such as electron beam evaporation or thermal evaporation can be used, but the modifications and changes based on the idea of the invention are still within the scope of the claims of the invention.
Claims (9)
1. The manufacturing method of the gallium oxide Schottky diode with low starting voltage is characterized by comprising the following steps of:
1) Sequentially cleaning the gallium oxide substrate (2) by acetone-isopropanol-deionized water;
2) The surface of the cleaned gallium oxide substrate (2) is subjected to surface restoration pretreatment so that the surface damage is restored, and a high-quality low-doped gallium oxide epitaxial layer is grown conveniently;
3) Carrying out epitaxial light doping on the front side of the pretreated gallium oxide substrate by adopting a Hydride Vapor Phase Epitaxy (HVPE) method to form a gallium oxide layer (3), depositing ohmic cathode metal (1) on the back side of the gallium oxide substrate by adopting magnetron sputtering, and annealing the ohmic cathode metal (1);
4) Performing laughing gas inductively coupled plasma technology treatment on the lightly doped gallium oxide layer (3) to form Ga-N covalent bonds on the surface of the lightly doped gallium oxide layer, namely a thin gallium nitride layer;
5) And forming an anode pattern on the lightly doped gallium oxide layer (3) after being treated by the laughing gas inductively coupled plasma technology by adopting a photoetching process, and adopting electron beam evaporation to deposit schottky anode metal (4) according to the anode pattern to finish the device manufacture.
2. The method according to claim 1, characterized in that: and 2) carrying out surface restoration pretreatment on the surface of the cleaned gallium oxide substrate (2), wherein the surface restoration pretreatment is realized as follows:
2a) Immersing the cleaned gallium oxide substrate (2) into a piranha solution prepared by mixing concentrated sulfuric acid with the concentration of 98% and hydrogen peroxide with the concentration of 30% according to the proportion of 3:1, and immersing for 10-40 minutes;
2b) And (3) annealing the gallium oxide substrate treated by the piranha in an oxygen atmosphere, wherein the annealing temperature is 600-1000 ℃ and the annealing time is 10-60 minutes.
3. The method according to claim 1, wherein: 4) The light doped gallium oxide layer (3) is treated by laughing gas inductive coupling plasma technology, and the process conditions are as follows:
the power is 50-500W, the laughing gas flow is 20-150sccm, the pressure is 4-20mtorr, the ambient temperature is 25-150 ℃, and the time is 2-20 minutes.
4. The method according to claim 1, wherein: 3) The hydride vapor phase epitaxy technology HVPE method is adopted to carry out epitaxy of the lightly doped gallium oxide layer (3) on the front surface of the pretreated gallium oxide substrate, and the implementation is as follows:
3a) HCl and high-purity metal Ga are reacted at 850 ℃ to produce GaCl and GaCl 3 ；
3b) GaCl and GaCl 3 React with oxygen at a temperature of 500-650 ℃ to produce an epitaxial layer of gallium oxide, which is deposited on a gallium oxide substrate (2).
5. The method according to claim 1, wherein: and 3) preparing ohmic metal on the back of the gallium oxide substrate (2) by adopting magnetron sputtering, wherein the metal is Ti/Au, the thickness of a first layer Ti close to the gallium oxide substrate layer is 20-50nm, and the thickness of a second layer Au metal is 100-400nm.
6. The method according to claim 1, wherein: 3) The ohmic cathode metal is annealed in nitrogen atmosphere at 400-500 deg.c for 1-3 min.
7. The method according to claim 1, characterized in that: the lightly doped gallium oxide layer (3) grown on the gallium oxide substrate (2) subjected to surface repair pretreatment in the step 3) has the thickness of 3-15 mu m and the doped carrier concentration of 10 16 -10 18 cm -3 。
8. The method according to claim 1, characterized in that: the gallium oxide substrate (2) has a thickness of 300-650 mu m and an effective doping carrier concentration of 10 18 -10 20 cm -3 The doping ion is Si ion or Sn ion.
9. The method according to claim 1, wherein: and 5) adopting electron beam evaporation to deposit schottky anode metal (4) according to the anode pattern, wherein the evaporation metal is Ni/Au, the thickness of the first layer of metal Ni is 45-60nm, and the thickness of the second layer of metal Au is 200-400nm.
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| CN112038416A (en) * | 2020-09-15 | 2020-12-04 | 西安电子科技大学 | Schottky diode based on p-type NiO film and inclined plane terminal structure and manufacturing method thereof |
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| CN112038416A (en) * | 2020-09-15 | 2020-12-04 | 西安电子科技大学 | Schottky diode based on p-type NiO film and inclined plane terminal structure and manufacturing method thereof |
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